perhaps one way is to avoid using postal data altogether. All header pages in electoral rolls(the first page) contain the name of the polling station related to that roll, the PS number, and importantly the pin code.
A site like psleci.nic.in has geog coordinates of polling stations (though Raphael had collected the data earlier*). Matching the two will give a fairly dense scattering of points - in fact much more dense than if we used some of the methods earlier in this thread. We thus have a way of associating a pin code with a geo coordinate. We can then use the voronoi method. Electoral rolls are mostly in pdf which make them difficult to scrape. But from what i have seen, for any given state, the location on the header page, of the pincode number is more or less constant, making it possible to target just that part of the page with any pdf parser. Electoral rolls have become difficult to download in bulk( a good thing!) but i understand different people on this group have the pdfs for different states. Putting this stuff together should give us comprehensive data on header pages for atleast some states. Alternatively, we can file RTIs for just the header pages of electoral rolls, though i dont know how successful that would be. * Raphael's data is at https://github.com/raphael-susewind/india-election-data On Sun, Mar 27, 2016 at 12:07 PM, srinivas kodali <iota.kod...@gmail.com> wrote: > Well, There were postal delivery zones in the past and the postal > department even used to make maps of these zones. The Delhi postal > delivery zone map > <https://drive.google.com/file/d/0B1RcWLku0ZOWWVBHMldrZWdfZEU/view?usp=sharing> > had > boundaries for delhi. I am not sure if other cities had them or how long > the postal department was doing this, but it certainly can help with the > boundaries for cities. > > Regards, > Srinivas Kodali > www.lostprogrammer.com > *"Not everyone who wanders is lost, I am probably a bit"* > > On Tue, Mar 22, 2016 at 9:29 PM, Arun Ganesh <arungra...@gmail.com> wrote: > >> Shravan, crowdsourcing the boundaries of pincodes is not as trivial as >> you think. To start with, an area does not fall under a pincode, rather a >> street does based on the post office that services it. Read this: >> http://www.georeference.org/doc/zip_codes_are_not_areas.htm >> >> You may also want to do some background reading of existing research that >> has been done by the group here: >> https://datameet.hackpad.com/M4hPFJVV2Gm?eid=v4YoXN4tTw5 >> >> To sum up, nobody has precise pincode boundaries like how you imagine >> them, not even the postal department. Any existing datasets are an estimate >> at best using some data processing on a large volume of address data. >> >> -- >> Datameet is a community of Data Science enthusiasts in India. Know more >> about us by visiting http://datameet.org >> --- >> You received this message because you are subscribed to the Google Groups >> "datameet" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to datameet+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > Datameet is a community of Data Science enthusiasts in India. Know more > about us by visiting http://datameet.org > --- > You received this message because you are subscribed to the Google Groups > "datameet" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to datameet+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- Datameet is a community of Data Science enthusiasts in India. Know more about us by visiting http://datameet.org --- You received this message because you are subscribed to the Google Groups "datameet" group. To unsubscribe from this group and stop receiving emails from it, send an email to datameet+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
